The vehicles collided on Hopkins Road at Truganina at about 9.15pm.
One person died at the scene, while three others were taken to hospital in a critical condition.
Another three were taken to hospital with serious injuries.
Police are investigating and detectives would like to speak with anybody who was in the area prior to the collision.
Anybody with information or relevant footage is urged to contact Crime Stoppers online or on 1800 333 000.
